Method

ABSTRACT

There is provided a process for the prevention and/or reduction of Maillard reaction in a foodstuff containing (i) a protein, a peptide or an amino acid and (ii) a reducing sugar, the process comprising contacting the foodstuff with an enzyme capable of oxidising a reducing group of the sugar.

RELATED APPLICATIONS

This application is a continuation-in-part of U.S. application Ser. No.10/001,136 filed Nov. 15, 2001 now U.S. Pat. No. 6,872,412, which claimspriority from U.S. Provisional Application 60/256,902 filed Dec. 19,2000 and United Kingdom Application 0028119.6 filed Nov. 17, 2000. Thepresent application is also a continuation-in-part of InternationalPatent Application No. PCT/IB2003/005278 filed Oct. 24, 2003 andpublished as WO 2004/039174 on May 13, 2004, which claims priority fromUnited Kingdom Application 0225236.9 filed Oct. 30, 2002 and U.S.Provisional Application No. 60/438,852 filed Jan. 9, 2003. All of theabove-mentioned applications, as well as all documents cited herein anddocuments referenced or cited in documents cited herein, are herebyincorporated herein in their entirety by reference.

FIELD OF THE INVENTION

The present invention relates to the control of Maillard reaction in afoodstuff.

BACKGROUND OF THE INVENTION

Foodstuffs consist of an extremely broad spectrum of constituents. Theseinclude

-   -   nitrogen-containing (proteinaceous) compounds (e.g. one or more        free amino acids or their derivatives, protein hydrolysates,        intact whole proteins, or a combination of these) plus vitamins,        including amino nitrogen containing vitamins, and their        derivatives, plus other, non-amino nitrogen-containing        compounds, e.g. ammonium compounds such as ammonium sulphate    -   carbohydrates, including        -   reducing sugars, e.g. glucose (also known as dextrose),            fructose (also known as levulose) and 5-carbon or pentose            sugars such as xylose, and other aldehyde containing            compounds which may be found, for example in flavouring            agents        -   non-reducing disaccharide sugars (e.g. sucrose) which may be            hydrolysed to produce the reducing sugar moiety, this            reaction being promoted by the presence of moisture and            elevated temperatures.

Over time, in the presence of moisture, and in even moderate heat (i.e.at temperatures above the freezing point of water), the Maillardreaction occurs.

The Maillard reaction is a reaction consisting of an a nucleophilicattack by a free amino group present in a protein, a peptide or an aminoacid on an aldehyde group of a reducing sugar. The reaction productsfurther cause a series of reactions with other proteinaceous aminogroups, thereby to form a brown material and to cause a crosslinkingbetween proteins. Historically, Maillard reported in 1912 that a mixedsolution of an amino acid and a reducing sugar, when heated, is colouredinto brown (L. C. Maillard, Compt. Rend. Soc. Biol., 72, 599 (1912))and, since then, the reaction is called Maillard reaction. In foodstuffsthe Maillard reaction typically comprises the interaction of thenitrogen compounds with the aldehyde groups of reducing sugars or othercarbonyl compounds.

In some instances, the browning of a Maillard reaction is desirable, forexample with butterscotch confections, caramel, cooked meats, etc. Inother instances this reaction is undesirable. For example the Maillardreaction can be problematic in some baked food items such as gratin andcakes in which this browning reaction is not easily controlled. This mayresult in the attractive brown colour becoming too dark and producingblack blisters. Clearly this is not desirable.

Furthermore the Maillard reaction can be problematic in the productionof foodstuffs containing a dairy product, in particular cheese, whichare cooked at a high temperature. In the area of pizza production thereis a pronounced Maillard reaction from the cheese spread on top of thepizza. In the present specification and indeed in the art pasta filetais referred to as mozzarella.

Many pizza manufacturers bake pizza at temperatures>260° C. At thesehigh temperatures the propensity of the cheese to brown excessively hasbecome a particular concern to the mozzarella industry because themozzarella manufacturers must deliver cheese that will not make blackblisters and brown areas when baked at these high temperatures.

The browning effect from mozzarella cheese is typically caused byresidual amount of reducing sugars lactose and galactose left from thecheese production. Therefore many attempts to reduce the browningreactions of mozzarella have been based on attempts to reduce the levelsof these sugars, and in particular the level of galactose, in thecheese.

In the traditional manufacture of mozzarella, during normal processingconditions, the fermenting micro-organism ferments only the glucose partof lactose and thus releases galactose into the medium. The cheese issubsequently washed during the manufacturing process, however, typicallygalactose and lactose remain in the cheese in an amount of 0.3 to 0.5wt. %. Dr. Norman Olson, Dairy Record, June 1983, p. 112-113 hasdiscussed that the degree of browning of mozzarella is related to thefree amino acids and sugar concentration in the cheese, and the browningcan be prevented by removing the reactants—usually sugar. He also refersto very strong correlation coefficient between galactose and colourlevels of baked cheese. Many attempts to reduce the level of galactoseand lactose in mozzarella are mentioned in the literature.

U.S. Pat. No. 3,531,297 discloses a process for manufacturing mozzarellacomprising the step of soaking the curd in warm water to extract lactosefrom the curd, and thereby reduce the final lactose content of thecheese. In general, the lower the lactose content of the finalmozzarella, the less tendency there is for the cheese to blister, burn,or char when it is subjected to high temperature baking.

While the process of U.S. Pat. No. 3,531,297 was used extensively on acommercial basis in the United States, and was a desirable commercialprocess, it does have certain disadvantages. The large curd soakingtanks add to the equipment and plant space costs, and the used soakwater, which contains lactose, lactic acid and other substances, can addconsiderably to the waste disposal burden of an operating plant. Anotherlimitation of the process of U.S. Pat. No. 3,531,297 is that the entireprocessing operation from the cheese vat to the mixer must be carefullytimed, sequenced, and carried out on a substantially continuous basis.In practice, this means that the operators of the plant must almostimmediately carry out the mixing of the cheese on the completion of thecurd soak.

U.S. Pat. No. 4,085,228 discloses a low-moisture mozzarella preparedusing a standard starter culture plus an additional culture selectedfrom Pediococcus cerevisiae, Lactobacillus plantarum, Streptococcusfaecalis, Streptococcus durans, and Lactobacillus casei, or mixturesthereof. Although the cheese is made by the usual processing steps, thecheese product has a reduced lactose sugar (and/or its monosaccharidederivatives) content due to the added culture, which metabolisesresidual lactose during a cold temperature holding at the end of theprocess. According to U.S. Pat. No. 4,085,228 the resulting cheese hasimproved properties for the manufacture of pizza, being substantiallynon-burning and having improving melt, flavour, and colourcharacteristics. However, the combination of two or more startercultures makes the mozzarella cheese production more complicated andmoreover, still the cheese will still contain minor amounts of galactoseand lactose, which can take part in a Maillard reaction.

Mukherjee, K. K.; Hutkins, R. W. Journal of Dairy Science 1994, 77(10)2839-2849 have shown that the use of a galactose-fermenting, galactosenon-releasing micro-organism as a starter culture can produce of lowbrowning mozzarella cheese. Galactose level below 0.1% in the mozzarellacheese was obtained by using selected micro-organism.

According to M. A. Rudan and D. M. Barbano, 1977 J. Dairy Sci81:2312-2319 the problem related to too much browning and scorching ofmozzarella is more pronounced when using low fat cheese (for examplecheese containing 0.25-5.8% fat) rather than using a full fat cheese(for example 21% fat). It is discussed that the problem of over-browningis caused by the cheese surface drying too fast which results inscorching. In Rudan et al. the problem was reduced by spraying a layerof vegetable oil on the mozzarella.

In a review A. H. Jana, Indian Dairyman 44, 3, 1992, p. 129-132 mentionsthe problems with browning of cheese on baked pizza. It is disclosedthat the problem is associated with residues of galactose and lactose inthe cheese. A number of measures are disclosed to minimise the problemby controlling the level of galactose. These measures include:

-   -   use of specific combinations of Streptococcus and Lactobacillus        bacteria which are able to ferment galactose. This will reduce        the level of galactose in the cheese.    -   improved washing of the curd with hot water 60-80° C. during the        final heating stage.    -   draining of the curd at pH>6.3 resulting in more of the        remaining lactose and galactose being fermented.    -   moderating the processing temperature in the manufacture of        processed mozzarella cheese.    -   prompt cooling of mozzarella cheese after moulding, leading to        controlled levels of galactose in the cheese.    -   reducing the brining period thus avoiding excess salt in the        water phase and allowing the lactic starter to ferment more of        the residual sugar.    -   storing the cheese for a minimum period to reduce the        proteolytic formation of free amino groups which are able to        react with galactose.

Many of the measures to minimise excessive browning mentioned by A. H.Jana are based on very strict process control or process modificationswhich are difficult to handle and/or may increase cost or decreaseyield.

The addition of enzymes to cheese during the production thereof is knownfrom the art. For example U.S. Pat. No. 5,626,893 teaches the use ofglucose oxidase as an oxygen scavenger in anticaking agent for cheese.

The present invention alleviates the problems of the prior art.

Some aspects of the invention are defined in the appended claims.

DETAILED DESCRIPTION OF THE INVENTION

We have found that the problems of excessive browning caused by Maillardreaction of foodstuffs containing a protein and a reducing sugar, inparticular baked food products, can be controlled by contacting thefoodstuff with an enzyme capable of oxidising the reducing group of thesugar. This is a novel approach in which reducing sugar is oxidised toavoid Maillard reaction by bringing the foodstuff into contact with anenzyme which is capable of performing the necessary oxidation andthereby eliminating the reducing sugar from the foodstuff by conversion.

In the present specification, by the term “prevention and/or reductionof Maillard reaction” it is meant that the extent of a Maillard reactionis reduced and/or the period of time required for completion of aMaillard reaction is increased.

In some aspects preferably the enzyme is capable of oxidising thereducing group of a monosaccharide and the reducing group of adisaccharide.

In some aspects preferably the enzyme is hexose oxidase (EC1.1.3.5) orglucose oxidase (EC1.1.3.4). In a highly preferred aspect the enzyme ishexose oxidase. Preferably the HOX is obtained or prepared in accordancewith WO 96/40935.

Hexose oxidase is preferred because glucose oxidase (GOX) has a muchhigher specificity for glucose and can not eliminate the possibleMaillard reaction caused by other sugar like galactose and lactose.Glucose oxidase therefore has limited application for reduction ofMaillard reaction in food systems. In dairy products such as cheese,galactose and lactose is mainly responsible for the Maillard reaction.

Hexose oxidase (HOX) is an carbohydrate oxidase originally obtained fromthe red alga Chondrus crispus. As discussed in WO 96/39851 HOX catalysesthe reaction between oxygen and carbohydrates such as glucose,galactose, lactose and maltose. Compared with other oxidative enzymessuch as glucose oxidase, hexose oxidase not only catalyse the oxidationof monosaccharides but also disaccharides are oxidised. (Biochemica etBiophysica Acta 309 (1973), 11-22).

The reaction of glucose with Hexose Oxidase isD-glucose+H₂O+O₂→δ-D-gluconolactone+H₂O₂

In an aqueous environment the gluconolactone is subsequently hydrolysedto form gluconic acid.

As shown, HOX oxidises the carbohydrate at the reducing end at carbon 1and thus eliminates the possible Maillard reaction of the carbohydrate.

In a preferred aspect of the present invention the enzyme is capable ofoxidising the sugar of the foodstuff at the 1 position. This aspect isadvantageous because it ensures that the reducing sugar is oxidised suchthat the reducing part of the sugar is no longer available to undergothe Maillard reaction. In contrast, for example, galactose oxidaseoxidises galactose at carbon 6 leaving the reducing end unchanged. AMaillard reaction therefore can also take place after a galactoseoxidase treatment. During cheese making galactose is often accumulatedbecause the micro-organism used to produce cheese can not digestgalactose. It might therefore be speculated that galactose oxidaseshould be able to eliminate galactose and reduce the tendency toMaillard reaction. However, in this preferred aspect of the presentinvention this is clearly not the case.

In some aspects preferably the reducing sugar is lactose or galactose.

In some aspects preferably the reducing sugar is galactose.

In some aspects preferably the foodstuff is selected from a dairyfoodstuff; milk based or milk containing foodstuff, such as gratin; anegg based foodstuff; an egg containing foodstuff; bakery foodstuffsincluding toasts, bread, cakes; and shallow or deep fried foodstuff suchas spring rolls.

When the foodstuff is a dairy foodstuff it is preferably cheese, morepreferably mozzarella cheese.

When the foodstuff is cheese the present invention is particularlyadvantageous. The enzyme of the present invention such as HOX is able toremove reducing sugars in cheese, for example in shredded cheese. Thusit will no longer be so critical to have residues of lactose left in thecheese. It is therefore possible to reduce the number of washings of thecheese curd during the production of the cheese. By reducing the numberof washings, the amount of wastewater is also reduced and the yield ofcheese is increased.

In some aspects preferably the foodstuff is a potato or a part of apotato. We have found that in the production of cooked potato productsthe application of the present enzyme reduces unwanted browning. Typicalpotato products in which the present invention may be applied are Frenchfries and potato chips (crisps).

The enzyme may be contacted with foodstuff during its preparation or itmay be contacted with the foodstuff after the foodstuff has beenprepared yet before the food stuff is subjected to conditions which mayresult in the undesirable Maillard reaction. In the former aspect theenzyme will be incorporated in the foodstuff. In the later aspect theenzyme will be present on the surface of the foodstuff. When present onthe surface Maillard reaction is still prevented as it is the surface ofa material exposed to drying and atmospheric oxygen which undergoes thepredominant Maillard reaction.

When contacted with foodstuff during its preparation the enzyme may becontacted at any suitable stage during its production. In the aspectthat the foodstuff is a dairy product it may be contacted with the milkduring acidification of the milk and precipitation of the milk curd. Inthis process the enzyme (such as HOX) is not active during the anaerobicconditions created during the acidification and milk proteinprecipitation, but will be active in the dairy product such as cheesewhen aerobic conditions are created. Once in aerobic conditions theenzyme oxidise the reducing sugar and reduce the tendency to Maillardreaction.

For application of the enzyme to the surface of the foodstuff, one mayapply the enzyme in any suitable manner.

Typically the enzyme is provided in a solution or dispersion and sprayedon the foodstuff. The solution/dispersion may comprise the enzyme in anamount of 1-50 units enzyme/ml, such as 1-50 units Hexose Oxidase/ml.

The enzyme may also be added in dry or powder form. When in wet or dryform the enzyme may be combined with other components for contact withthe foodstuff. For example when the enzyme is in dry form it may becombined with an anticaking agent.

In some aspects the present invention further comprises the step ofcontacting the foodstuff with a catalase.

In a preferred aspect the foodstuff is packaged within an oxygenimpermeable container after contact with the enzyme. We have identifiedthat the enzyme on action with the reducing sugar consumes oxygen withina container. Consumption of the oxygen will reduce the microbiologicalactivity in the foodstuff and improve the shelf life. The normalpractice of packaging in controlled atmosphere may then be dispensedwith.

When the foodstuff is packaged within an oxygen impermeable containerafter contact with the enzyme it is important that the foodstuff eitherbe allowed to stand before packaging or be packaged with an amount ofoxygen within the container. The ant-Maillard reaction which occurs inthe present process involves the oxidation of the reducing group of asugar. For this reaction to occur oxygen is required. If the foodstuffis packaged without standing or without an amount of oxygen within thecontainer, this anti-Maillard reaction may not proceed and thebeneficial effects of the present invention may be reduced.

We have also found that the enzyme of the present invention such as HOXmay be sufficiently active at low temperatures such that the foodstuffmay be refrigerated or frozen after contact with the enzyme without theneed to allow the enzyme/reducing sugar reaction to proceed at roomtemperatures. This is clearly advantageous for the production offoodstuffs where maintenance at elevated temperature may result inunacceptable growth of micro-organisms. Thus in a preferred aspect theprocess comprises cooling the foodstuff to a temperature of no greaterthan 5° C. when the majority of the reducing sugar present in thefoodstuff contacted with the enzyme has not been oxidised by the enzyme.

It will be appreciated by one skilled in the art that in the practice ofthe present invention one contacts the foodstuff with a sufficientamount of enzyme to prevent and/or reduce a Maillard reaction. Typicalamounts of enzyme which may be contacted with the foodstuff are from0.05 to 5 U/g (units of enzyme per gram of foodstuff), from 0.05 to 3U/g, from 0.05 to 2 U/g, from 0.1 to 2 U/g, from 0.1 to 1.5 U/g, andfrom 0.5 to 1.5 U/g.

The present invention will now be described in further detail by way ofexample.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows photographs;

FIG. 2 shows photographs;

FIG. 3 shows photographs;

FIG. 4 shows photographs;

FIG. 5A shows photographs;

FIG. 5B shows photographs;

FIG. 6 shows photographs;

FIG. 7 shows photographs;

FIG. 8 shows photographs;

FIG. 9 shows a graph;

FIG. 10 shows a photograph;

FIG. 11 shows a graph;

FIG. 12 shows a graph;

FIG. 13 shows a graph;

FIG. 14 shows a photograph;

FIG. 15 shows a photograph; and,

FIG. 16 shows a diagram.

EXAMPLES

Image Analyses

Image analysis of the samples of the Examples was performed as follows.

Images of samples are recorded in calibrated non-scattering lightintensity by a three chip CCD colour RGB video camera with a resolutionof 440000 pixels (JVC KY-F58E). Calibration is done with Kodak's GrayScale. Through computer based image analysis (Adobe Photoshop includingPlug Ins) the images are prepared for quantitative colour measurement ofthe sample expressed as mean colour intensity of the whole sample, themean colour intensity of the browned part of the sample and furthermorethe relative area of the browned part is calculated. During browning ofthe sample the green colour intensity decreases significantly andbrowned areas are then defined as areas with green colour intensity lessthan 100. The total colour intensity range is from 0-255 (8 bitresolution), where 0 is no intensity and 255 is full intensity. Thecalibrated light intensity secures that measurements in different seriesare comparable.

The colour intensity for each pixel is calculated as the average valueof the intensities for the red, green and blue colour.

The mean colour intensity is then calculated as the average colourintensity of all the pixels in the sample and in the browned part of thesample respectively. The relative browned area is calculated as theratio between the number of pixels in the browned part of the sample andthe total number of pixels in the whole sample.

Examples 1 Pizza with Mozzarella Cheese

20 g mozzarella cheese (Karoline's Dansk mozzarella, 25% protein, 1%carbohydrate and 21% fat) was scaled in a beaker. 1 ml Hexose Oxidasesolution (7.5 HOX units/ml) was sprayed onto the cheese. As a control 1ml water was sprayed onto another sample of mozzarella cheese. Thecheese was stored for 2 hours at room temperature. A dough was made fromflour, salt and water. 10 g dough was scaled and placed in a petri dish.5 grams of mozzarella cheese was placed on top of the dough and baked at225° C. for 7 min. Another sample was baked for 15 min. After baking thesamples were evaluated subjectively. The samples are shown in FIG. 1.

From this test it was clear that the application of hexose oxidase tothe cheese reduced the tendency to brown as a result of reduced Maillardreaction. Moreover, in samples which were browned the present inventionprovided a more even brown colouring without black scorching.

Example 2

Mozzarella cheese was treated in the manner listed in Table 1 using theprocedure described in Example 1.

TABLE 1 Test Water, HOX Storage Storage no Cheese, g g U/g cheese time,hr. temperature, ° C. 1 30 1.3 0 20 20 2 30 1.3 0.01 20 20 3 30 1.3 0.0520 20 4 30 0 20 20 5 30 1.3 0.01 20 5 6 30 1.3 0.05 20 5 7 30 1.3 0.3 205 8 30 1.3 0.3 20 5

After the treatment the cheese samples were placed on a dough and bakedfor 12 minutes at 225° C. After baking the samples were evaluatedsubjectively. The samples obtained are shown in FIG. 2.

The results show that 0.05 U HOX per g cheese is clearly sufficientreduce the browning of the cheese stored at 20° C. The results alsoshows that the browning is reduced even if the cheese treated with HOXis stored at 5° C.

Example 3

Mozzarella cheese was treated in the manners listed in Table 2 using theprocedure described in Example 1.

TABLE 2 Test no. Cheese, g Enzyme 1 20 Control, 1 ml water 2 20 1 mlHexose Oxidase, 0.75 Units/ml 3 20 1 ml Galactose Oxidase, 63 Units/ml 420 1 ml Glucose oxidase 260 Units/ml

After 20 hours storage at 20° C. the cheese samples were applied onto adough and baked at 225° C. for 7 minutes. The baked mozzarella sampleswere evaluated subjectively. The samples obtained are shown in FIG. 3.

The results clearly illustrate that hexose oxidase is very efficient inreducing the extent of Maillard reaction. Glucose oxidase and galactoseoxidase only have limited impact on the extent of Maillard reaction.

Example 4

The following example was performed in order to investigate the effectof applying enzyme, in particular hexose oxidase, at differentconditions. We studied whether the manner of application of hexoseoxidase onto mozzarella cheese might be a critical parameter for theprevention of Maillard reaction in mozzarella cheese normally stored at5° C. and packed under controlled conditions.

The tests of Table 3 were performed using mozzarella cheese (Karoline'sDansk mozzarella, 25% protein, 1% carbohydrate and 21% fat).

TABLE 3 Test Hexose Oxidase Resting time, hr Packing no. Unit/g cheesebefore packing Condition 1 0.1 0.5 Air 2 1 0.5 Air 3 Control 1.5 Air 40.1 3 Air 5 1 3 Air 6 0.1 0.5 Vacuum 7 1 0.5 Vacuum 8 Control 1.5 Vacuum9 0.1 3 Vacuum 10 1 3 Vacuum

The samples were packed in aluminium bags. Half of the samples werevacuum packed and the other half were packed with normal atmosphericair. All samples were stored at 5° C. After 1 week storage the cheesesamples were baked for 12 minutes in the manner described in Example 1.After baking the samples were evaluated. The samples obtained are shownin FIG. 4.

The results clearly illustrate the effect of adding HOX to the cheese.The results further show that reduction in Maillard reaction may beobtained for products packed in air and products packed under a vacuumafter a resting period.

Example 5

The effect of hexose oxidase on browning was tested in a gratin made bythe following procedure.

75 g shortening (mp. 35° C.) and 100 g flour were heated in a pot duringmixing. 350 ml skim milk (preheated to 90° C.) was added duringcontinued mixing. Salt and pepper was added. 4 eggs were divided intoyolk and egg white. The egg yolks were added individually. The egg whitewas whipped to a foam with 10 gram baking powder and mixed carefullyinto the dough. The dough was placed in 2 aluminium trays. One of thetrays was sprayed with a solution of hexose oxidase 7.5 Units/ml andkept at room temperature for 30 minutes. The gratin was then baked in aair circulating oven at 175° C. for 20 minutes. After baking the gratinwas evaluated visually. The samples obtained are shown in FIG. 5A.Further sample were treated in the manner of Table 6 below.

TABLE 6 Sample Enzyme added Mean Brown Colour 1 0.1 ml water 117 2 0.1ml HOX solution 0.75 U/ml 109 3 0.1 ml HOX solution 1.50 U/ml 111 4 0.1ml HOX solution 7.50 U/ml 134 5 Control 116

After baking the gratin was evaluated visually. The samples obtained areshown in FIG. 5B. The mean brown colour measurements performed by imageanalysis indicate that HOX solution containing 7.5 U/ml gives less browncolour (higher values indicate less browning). The other values for meanbrown colour are not significantly different form the control.

The results show that the application of HOX gives a less dark surfaceof the gratin indicating that the Maillard reaction is reduced.

Example 6

The effect of HOX on browning of mozzarella was tested in a low fatmozzarella cheese (Cheasy: 13% fat, 33% protein and 1.5% carbohydrates).The cheese samples were given the following treatment

-   1: Control 1 ml water added to 20 gram cheese-   2: 0.2 ml HOX (7.5 Units/ml) to 20 gram cheese.-   3: 1 ml HOX (7.5 Units/ml) to 20 gram cheese.

The enzyme was applied onto the cheese by spraying a solution of theenzyme onto the shredded cheese. The samples were stored at 5° C. for 20hours and then placed onto a dough in an aluminium tray and baked for 10minutes at 225° C. in an air circulating oven. After baking the sampleswere evaluated. The samples are shown in FIG. 6.

The results clearly illustrate the ability of HOX to reduce theexcessive browning of a low fat mozzarella cheese. It is also clear thatthe reduction of browning is dependent on the dosage of hexose oxidase.

Example 7

The effect of hexose oxidase on browning of mozzarella was studied byspraying different level of HOX onto mozzarella cheese. After sprayingthe HOX solution the cheese was stored for 30 minutes or 3 hours at roomtemperature and then vacuum packed in an aluminium bag. After 14 daysstorage at 5° C. the cheese samples were placed on top of a pizza doughand baked for 8 minutes at 225° C. After baking the samples wereevaluated visually and pictures of the samples were analysed by a imageanalyser. The samples of this experiment are shown in FIG. 7: Theresults of the image analysis are given in Table 7

TABLE 7 Hexose Resting Mean % Test Oxidase time, hr Mean Pizza BrownBrown no. Unit/g cheese before packing Colour colour area 1 0.1 0.5 125106 61 2 0.1 3 146 122 22 3 1 0.5 173 125 0.9 4 1 3 172 127 0.6 5Control 1.5 123 107 63

As shown in FIG. 7 the browning reaction is strongly reduced by additionof hexose oxidase to the mozzarella cheese. It is also clear that thebrowning is dependent on the dosage of HOX. It is also observed that theresting time before vacuum packing is important. In particular, at adosage of 0.1 U/g a resting time of 0.5 h before packaging appears notto be sufficient to substantially reduce Maillard browning. However aresting time of 3 h at this dosage is sufficient. At a dosage of 1 U/g aresting time of either 0.5 h or 3 h before packaging significantlyreduces Maillard browning. The differences shown in FIG. 7 are confirmedby the mean colour measurement where lower value indicate a more brownproduct. Also the % of browned area is also strongly influenced by theaddition of HOX to the cheese.

Example 8

Assay Method for Determination of Hexose Oxidase Activity (HOX Assay)

Principle. The HOX assay is based on the measurement of hydrogenperoxide generated in the oxidation of glucose. The hydrogen peroxide isoxidised with ABTS in presence of peroxidase to form a dye.

Reagents

-   1. 100 mM phosphate buffer, pH 6.3-   2. 55 mM D-glucose (SIGMA, G-8270) in 100 mM phosphate buffer, pH    6.3-   3. ABTS (SIGMA, A 1888), 5.0 mg/ml in distilled water-   4. Peroxidase (SIGMA, P-6782), 0.10 mg/ml in 100 mM phosphate    buffer, pH 6.3    Substrate:-   4.600 ml reagent 2-   0.200 ml reagent 3-   0.200 ml reagent 4    Assay-   290 μl Substrate and-   10 μl enzyme solution

The reaction is initiated by the addition of enzyme solution. Themixture is incubated at 25° C. and kinetics of the reaction are measuredfor 10 minutes on a spectrophotometer (405 nm). The blank samplecontains all the components except for the enzyme solution which isreplaced by water. From the measurement the slope of OD/min curve iscalculated.

Hydrogen Peroxide Standard Curve

A hydrogen peroxide standard curve can be constructed by using varyingconcentrations of freshly prepared H₂O₂ solution (MERCK perhydrol107298). One unit of enzyme activity is defined as the amount of enzymewhich produced 1 μmol of H₂O₂ per min at 25° C.

Example 9

The effect of HOX on browning of pizza cheese was tested in combinationwith catalase. The purpose of adding catalase in combination with HOX isto eliminate hydrogen peroxide formed by the catalytic conversion oflactose and galactose to the corresponding acids, because hydrogenperoxides may engage in some unwanted side reactions and create offflavour by for example lipid oxidation.

Catalase catalyses the following reaction:

In this experiment 60 g Mozzarella cheese (Karolina's Dansk Mozzarella,25% protein, 1 g carbohydrate and 21% fat) was treated with the amountsof enzyme shown in Table 7

TABLE 7 Test no. Units HOX/g cheese Units Catalase/g cheese 1 0 0 2 0.50 3 0 1 4 0.5 1 5 0.17 0.33

The catalase used is from Sigma cat. No. C3515.

Procedure: Enzyme solutions of HOX and catalase were sprayed onto themozzarella cheese, and then stored at room temperature for 2 hours. 8gram of the enzyme treated cheese is then placed on top of 16.7 gram ofdough in an aluminium tray and baked at 275° C. for 6 minutes.

The results of the baking experiments are shown in FIG. 8.

From the results in FIG. 8 it is clear that the addition of 0.5 U HOX/gcheese (test 2) reduces the Maillard reaction and gives less browning ofthe cheese. The same effect is also seen when 0.5 U HOX/g is combinedwith 1 U Catalase/g (test 4). Catalase alone (test 3) do not contributeto any reduction in Maillard reaction.

Example 10

In the above Examples we have shown that HOX is able to oxidise reducingsugars in Mozzarella cheese and thus reduce the tendency to Maillardreaction when Mozzarella cheese is baked.

In these experiments HOX was applied by spraying a solution of HOX ontothe cheese. This may create problems of handling because the cheesebecomes wet and sticky this may be limit the application of the shreddedcheese to pizza or other food items.

To overcome this problem we applied HOX to Mozzarella cheese in powderform. This is a very convenient way to add the enzyme because ananticaking agent such as starch is normally added to shredded cheeselike Mozzarella to avoid stickiness during storage.

In the following experiment HOX was added as a powder to Mozzarellacheese at two concentration 1 U/g and 0.1 U/g cheese and at 25 and 5° C.

Experimental

HOX in powder form is mixed with potato starch. 1.5 g potato starch withHOX is mixed with 98.5 g Mozzarella cheese to give a final dosage of 1unit or 0.1 unit HOX pr gram cheese. As a control Mozzarella cheese ismixed with potato starch without any HOX.

Example 10a

100 g cheese is placed in a blue cap bottle (310 ml) and an oxygensensor is placed in the bottle with a sealed cap. Oxygen consumption asa function of time is recorded.

1 U HOX/g cheese was tested at 25° C. and the oxygen level in thebottles registered as a function of time FIG. 9. This result clearlyillustrate that HOX is also active when it is added as a powder to thecheese. This is surprising as it might be speculated that HOX added as apowder under conditions with lower water activity may be less efficient.

As shown in FIG. 9 all the oxygen in the bottle is consumed by HOX.

Based on the volume of air in the bottle it is calculated that 0.018 moloxygen is consumed. From the knowledge that HOX oxidises one mol lactoseduring consumption of one mol oxygen it is calculated that 0.62% lactoseis oxidised. From the knowledge about typical level of remaining sugarin Mozzarella cheese it is concluded that almost all the reducing sugaris oxidised. This provides evidence that that diffusion of sugar or HOXoccurs with in the cheese.

Example 10b

After one day, 10 g cheese is placed in a aluminium tray and baked at275° C. for 6 minutes. Results from the baking test are shown in FIG.10. FIG. 10 clearly shows that HOX reduces the browning effect duringbaking.

Example 10c

In the next experiment only 0.1 U HOX/g cheese was added, and 100 gcheese was stored at 25° C. in a closed bottle (310 ml) with an oxygensensor. The oxygen consumption was followed as a function of time asshown in FIG. 11.

As expected the reaction was slower because of the lower HOX addition,but also in this experiment it was clear that a main part of theremaining sugar was oxidised within one day.

Example 10d

As cheese is normally stored in a refrigerator after being packed it isof interest to know whether HOX also under these conditions is able tooxidise reducing sugars in cheese.

In this experiment 1 U HOX/g cheese was added to Mozzarella cheese, and100 g cheese was stored at 5° C. in a closed bottle (310 ml) with anoxygen sensor. The oxygen consumption was followed as a function of timeas shown in FIG. 12.

The results in FIG. 12 clearly show that HOX is active at 5° C. duringconsumption of all the oxygen in the bottle. From a production point ofview this might be of benefit, because the reaction does not rely onkeeping the temperature at room temperature or higher, but the cheesetreated with HOX can immediately be stored at 5° C. where reducingsugars are oxidised to the corresponding acid, which will reduce theability of the cheese to produce Maillard reaction when the cheese isbaked. As a further benefit the oxygen in the package is consumed, whichwill reduce the microbiological activity in the cheese and improve theshelf life, and packaging in controlled atmosphere might be dispensedwith.

Based on the oxygen measurements in the bottles with cheese it ispossible to calculate the velocity of oxidation expressed as oxygenconsumption per minute.

In FIG. 13 the oxidation velocity is shown to cheese treated with HOX atdifferent conditions.

The reaction rate at 25° C. is as expected higher than at 5° C. when 1 UHOX/g cheese is added, and it is expected that the diffusion ofsubstrate and enzyme, not the enzyme concentration, which are thelimiting factors.

When 0.1 U HOX/g is added the change in oxidation rate is much smallerand this indicate that at this dosage there is a balance between enzymeactivity and substrate diffusion in the cheese.

Example 11

The consumption of fried potato as French fries (pommes frites) andpotato chips (crisps) has increased significantly during the past twodecades. One of the important parameters in the production of friedpotatoes is level of reducing sugar. The level should remain low,because high level of reducing sugar create more Maillard reactionswhich contribute to unrequired levels of browning.

In order to prevent an increase in the level of reducing sugar inpotatoes during storage potatoes are often sprayed with a herbicidecalled chlorpropham, which prevents the potato from sprouting. Sproutinginduces amylases in the potato which in turn form reducing sugars.

In this study it was investigated if it is possible to improve theappearance of fried potatoes by adding HOX to sliced potatoes beforefrying.

Procedure

Organic grown potatoes were used in order to ensure that no herbicideshas been used. The potatoes were peeled and sliced into 2 mm thickslices using a food processor. Half of the slices were immersed in awater solution of HOX containing 100 Units/ml for 3 minutes. The otherhalf of the potato slices was immersed in water for 3 minutes. Theslices were then stored in a closed container for over night (16 hours)and then fried in vegetable oil for 2 minutes at 180° C.

Results

When these potato slices are fried in oil at 180° C. for 2 minutes thepotato chips show some differences as shown in FIGS. 15 and 16.

The very brown areas of FIG. 14 is explained by a thinner potato slicein these areas and should not be taken into account for the evaluation.It is clear that potato slice treated with HOX produces a more goldensurface compared with the control which is more greyish. The differencesin appearance are clearer in FIG. 15 in which the golden surface of theHOX treated slice is clearly different from the control.

Conclusion

Fried potato slices prepared from potato slices treated with HOX have alighter and more golden surface compared with control. More pronouncedeffects of HOX treatment are expected if the potatoes were sproutedbefore frying.

Example 12 Treatment of 10 kg Potato Chips by Enzyme Incubator

This example relates to treating potato chips before frying in an enzymeincubator containing an oxidoreductase utilizing any of the followingsugars as substrate (glucose, maltose, sucrose and fructose) includingbut not limited to Hexose oxidase (EC 1.1.3.5) or Glucose oxidase (EC1.1.3.4).

Catalase (EC 1.11.1.6) may be added in catalytic amounts with the mainpurpose of regeneration oxygen to a maximum level of the molarsolubility in the incubation fluid (and to remove hydrogen peroxide).

Potato chips are immersed in the incubator containing a large body ofwater and/buffer with enzyme(s). Temperature and pH may be regulated asinstrumentally possible. Beneath the incubator is an inlet for air oroxygen. The amount of enzyme and/or incubation time may be determineddepending on the ratios oxygen saturation/enzyme amount/potato chipamount/incubator volume.

Materials:

-   -   1 HOX unit (umol H₂O₂/min)    -   1 Catalase unit (umol O₂ produced/min)    -   Molar solubility of oxygen (O2) (ambient T, P and salinity):        approx 250 μmol/L    -   thinly sliced potatoes (100 g of potatoes contain approximately        1×10−3 moles of sugar substrate for HOX)        Incubation Procedure:

100 U of HOX and 100 U of catalase (commercial products) are added to 1L of water at 25° C. Oxygen flow is set at a minimum of 0.015 L/minthrough a very fine grating. As vigorous stirring as possible which doesnot result in damage to the chips is implemented. Portions of 100 g areincubated for 10 minutes to a total of 100×10 min before changing theincubation solution. Alternatively sodium hydroxide or other base isadded directly to the incubation solution at a rate to keep the pH at 6(measured continuously).

The potatoes are sunsequently gently flushed with water and fried.

Using catalase combined with oxygen/air bubbling in the incubator allowsfor the following reduction in acrylamide. Levels of sugars are forwhite potato, boiled, without skin. Sugars are listed as the molarpercentage left to react following treatment. Molar ratio ofsugar:acrylamide is 1:1. Listed is the remaining level of acrylamidfollowing frying as a result of treatment in the enzyme incubator.

Treatment fructose glucose sucrose maltose acrylamide None 21.07 30.6936.3 12.07 100 GOX 21.07 0 36.3 12.07 69 HOX 21.07 0 36.3 6.04 63

The invention will now be further described by the following numberedparagraphs:

-   1. A process for the prevention and/or reduction of Maillard    reaction in a foodstuff containing (i) a protein, a peptide or an    amino acid and (ii) a reducing sugar, the process comprising    contacting the foodstuff with an enzyme capable of oxidising a    reducing group of the sugar.-   2. A process according to paragraph 1 wherein the enzyme is capable    of oxidising the reducing group of a monosaccharide and the reducing    group of a disaccharide.-   3. A process according to paragraph 1 or 2 wherein the enzyme is    capable of oxidising the sugar at the 1 position.-   4. A process according to paragraph 1, 2 or 3 wherein the enzyme is    hexose oxidase (EC1.1.3.5).-   5. A process according to any one of paragraphs 1 to 4 wherein the    reducing sugar is lactose or galactose.-   6. A process according to paragraph 5 wherein the reducing sugar is    galactose.-   7. A process according to any one of the preceding paragraphs    wherein the foodstuff is a dairy foodstuff.-   8. A process according to any one of the preceding paragraphs    wherein the foodstuff is cheese.-   9. A process according to any one of the preceding paragraphs    wherein the foodstuff is mozzarella cheese.-   10. A process according to any one of paragraphs 1 to 6 wherein the    foodstuff is a potato or a part of a potato.-   11. A process according to any one of the preceding paragraphs    wherein the enzyme is contacted with the foodstuff during the    production of the foodstuff.-   12. A process according to any one of paragraphs 1 to 10 wherein the    enzyme is contacted with the foodstuff after production of the    foodstuff.-   13. A process according to paragraph 12 wherein the enzyme is    sprayed on the foodstuff as a solution or dispersion.-   14. A process according to paragraph 13 wherein the    solution/dispersion comprises the enzyme in an amount of 1-50 units    Hexose Oxidase/ml.-   15. A process according to any one of the preceding paragraphs    wherein the process further comprises the step of contacting the    foodstuff with a catalase.-   16. Use of an enzyme for the prevention and/or reduction of Maillard    reaction in a foodstuff containing (i) a protein, a peptide or an    amino acid and (ii) a reducing sugar, wherein the enzyme is capable    of oxidising a reducing group of the sugar.-   17. A foodstuff prepared in accordance with the invention of any one    of the preceding paragraphs.-   18. A process as substantially hereinbefore described with reference    to any one of Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11.-   19. A use as substantially hereinbefore described with reference to    any one of Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11.-   20. A foodstuff as substantially hereinbefore described with    reference to any one of Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or    11.-   21. An oxygen impermeable container containing a foodstuff as    substantially hereinbefore described with reference to any one of    Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11.-   22. A process for preventing a Maillard reaction in a foodstuff    containing (i) a protein, a peptide, or an amino acid, and (ii) a    reducing sugar, comprising contacting the foodstuff with hexose    oxidase (EC1.1.3.5).-   23. The process according to paragraph 22, wherein the reducing    sugar is lactose or galactose.-   24. The process according to paragraph 23, wherein the reducing    sugar is galactose.-   25. The process according to paragraph 23, wherein the reducing    sugar is lactose.-   26. The process according to paragraph 22, wherein the foodstuff is    dairy foodstuff.-   27. The process according to paragraph 22, wherein the foodstuff is    milk based or milk containing foodstuff.-   28. The process according to paragraph 22, wherein the foodstuff is    cheese.-   29. The process according to paragraph 22, wherein the foodstuff is    mozzarella cheese.-   30. The process according to paragraph 22, wherein the foodstuff    contains amino acid.-   31. The process according to paragraph 30, wherein the amino acid is    asparagine.-   32. The process according to paragraph 22, wherein the enzyme is    contacted with the foodstuff during the production of the foodstuff.-   33. The process according to paragraph 22, wherein the enzyme is    contacted with the foodstuff after production of the foodstuff.-   34. The process according to paragraph 33, wherein the enzyme is    sprayed on the foodstuff as a solution or dispersion.-   35. The process according to paragraph 34, wherein the solution or    dispersion comprises the enzyme in an amount of 1-50 units Hexose    Oxidase/ml.-   36. The process according to paragraph 22, wherein the process    further comprises the step of contacting the foodstuff with a    catalase.-   37. The process according to paragraph 22, wherein the process    further comprises the step of heating the foodstuff which has been    contacted with hexose oxidase to a temperature of at least 175° C.-   38. The process according to paragraph 22, wherein the process    further comprises the step of heating the foodstuff which has been    contacted with hexose oxidase to a temperature of at least 225° C.-   39. The process according to paragraph 22, wherein the process    further comprises the step of heating the foodstuff which has been    contacted with hexose oxidase to a temperature of greater than 260°    C.-   40. A foodstuff prepared in accordance with the invention in any one    of paragraphs 22-39.-   41. A process for preventing a Maillard reaction in a foodstuff that    is heated containing (i) a protein, a peptide, or an amino acid,    and (ii) a reducing sugar, comprising contacting the foodstuff with    hexose oxidase (EC1.1.3.5), prior to heating.-   42. The process according to paragraph 41, wherein the reducing    sugar is lactose or galactose.-   43. The process according to paragraph 42, wherein the reducing    sugar is galactose.-   44. The process according to paragraph 42, wherein the reducing    sugar is lactose.-   45. The process according to paragraph 41, wherein the foodstuff is    dairy foodstuff.-   46. The process according to paragraph 41, wherein the foodstuff is    milk based or milk containing foodstuff.-   47. The process according to paragraph 41, wherein the foodstuff is    cheese.-   48. The process according to paragraph 41, wherein the foodstuff is    mozzarella cheese.-   49. The process according to paragraph 41, wherein the foodstuff    contains amino acid.-   50. The process according to paragraph 49, wherein the amino acid is    asparagine.-   51. The process according to paragraph 41, wherein the enzyme is    contacted with the foodstuff during the production of the foodstuff.-   52. The process according to paragraph 41, wherein the enzyme is    contacted with the foodstuff after production of the foodstuff.-   53. The process according to paragraph 52, wherein the enzyme is    sprayed on the foodstuff as a solution or dispersion.-   54. The process according to paragraph 53, wherein the solution or    dispersion comprises the enzyme in an amount of 1-50 units Hexose    Oxidase/ml.-   55. The process according to paragraph 41, wherein the process    further comprises the step of contacting the foodstuff with a    catalase.-   56. The process according to paragraph 41, wherein the heating is to    a temperature of at least 175° C.-   57. The process according to paragraph 41, wherein the heating is to    a temperature of at least 225° C.-   58. The process according to paragraph 41, wherein the heating is to    a temperature of greater than 260° C.-   59. A foodstuff prepared in accordance with the invention in any one    of paragraphs 41-58.-   60. A process for reducing the occurrence of a Maillard reaction in    a foodstuff containing (i) a protein, a peptide, or an amino acid,    and (ii) a reducing sugar, comprising contacting the foodstuff with    hexose oxidase (EC1.1.3.5) (HOX), wherein the reducing is in    comparison with a foodstuff that has not been contacted with HOX.-   61. The process according to paragraph 60, wherein the reducing    sugar is lactose or galactose.-   62. The process according to paragraph 61, wherein the reducing    sugar is galactose.-   63. The process according to paragraph 61, wherein the reducing    sugar is lactose.-   64. The process according to paragraph 60, wherein the foodstuff is    dairy foodstuff.-   65. The process according to paragraph 60, wherein the foodstuff is    milk based or milk containing foodstuff.-   66. The process according to paragraph 60, wherein the foodstuff is    cheese.-   67. The process according to paragraph 60, wherein the foodstuff is    mozzarella cheese.-   68. The process according to paragraph 60, wherein the foodstuff    contains amino acid.-   69. The process according to paragraph 68, wherein the amino acid is    asparagine.-   70. The process according to paragraph 60, wherein the enzyme is    contacted with the foodstuff during the production of the foodstuff.-   71. The process according to paragraph 60, wherein the enzyme is    contacted with the foodstuff after production of the foodstuff.-   72. The process according to paragraph 71, wherein the enzyme is    sprayed on the foodstuff as a solution or dispersion.-   73. The process according to paragraph 72, wherein the solution or    dispersion comprises the enzyme in an amount of 1-50 units Hexose    Oxidase/ml.-   74. The process according to paragraph 60, wherein the process    further comprises the step of contacting the foodstuff with a    catalase.-   75. The process according to paragraph 60, wherein the process    further comprises the step of heating the foodstuff which has been    contacted with hexose oxidase to a temperature of at least 175° C.-   76. The process according to paragraph 60, wherein the process    further comprises the step of heating the foodstuff which has been    contacted with hexose oxidase to a temperature of at least 225° C.-   77. The process according to paragraph 60, wherein the process    further comprises the step of heating the foodstuff which has been    contacted with hexose oxidase to a temperature of greater than 260°    C.-   78. A foodstuff prepared in accordance with the invention in any one    of paragraphs 60-77.-   79. A process for reducing the occurrence of a Maillard reaction in    a foodstuff that is heated containing (i) a protein, a peptide, or    an amino acid, and (ii) a reducing sugar, comprising contacting the    foodstuff with hexose oxidase (EC1.1.3.5) (HOX), prior to heating,    wherein the reducing is in comparison with a foodstuff that has not    been contacted with HOX.-   80. The process according to paragraph 79, wherein the reducing    sugar is lactose or galactose.-   81. The process according to paragraph 80, wherein the reducing    sugar is galactose.-   82. The process according to paragraph 80, wherein the reducing    sugar is lactose.-   83. The process according to paragraph 79, wherein the foodstuff is    dairy foodstuff.-   84. The process according to paragraph 79, wherein the foodstuff is    milk based or milk containing foodstuff.-   85. The process according to paragraph 79, wherein the foodstuff is    cheese.-   86. The process according to paragraph 79, wherein the foodstuff is    mozzarella cheese.-   87. The process according to paragraph 79, wherein the foodstuff    contains amino acid.-   88. The process according to paragraph 87, wherein the amino acid is    asparagine.-   89. The process according to paragraph 79, wherein the enzyme is    contacted with the foodstuff during the production of the foodstuff.-   90. The process according to paragraph 79, wherein the enzyme is    contacted with the foodstuff after production of the foodstuff.-   91. The process according to paragraph 90, wherein the enzyme is    sprayed on the foodstuff as a solution or dispersion.-   92. The process according to paragraph 91, wherein the solution or    dispersion comprises the enzyme in an amount of 1-50 units Hexose    Oxidase/ml.-   93. The process according to paragraph 79, wherein the process    further comprises the step of contacting the foodstuff with a    catalase.-   94. The process according to paragraph 79, wherein the heating is to    a temperature of at least 175° C.-   95. The process according to paragraph 79, wherein the heating is to    a temperature of at least 225° C.-   96. The process according to paragraph 79, wherein the heating is to    a temperature of greater than 260° C.-   97. A foodstuff prepared in accordance with the invention in any one    of paragraphs 79-96.

All publications mentioned in the above specification are hereinincorporated by reference. Various modifications and variations of thedescribed methods and system of the invention will be apparent to thoseskilled in the art without departing from the scope and spirit of theinvention. Although the invention has been described in connection withspecific preferred embodiments, it should be understood that theinvention as claimed should not be unduly limited to such specificembodiments. Indeed, various modifications of the described modes forcarrying out the invention which are obvious to those skilled inchemistry or related fields are intended to be within the scope of thefollowing claims.

1. A process for reducing a Maillard reaction and hence browning incheese that is heated to at least melting comprising contacting thecheese with an enzyme prior to heating, wherein the improvementcomprises the enzyme being hexose oxidase (EC1.1.3.5).
 2. The processaccording to claim 1, wherein the cheese is mozzarella cheese.
 3. Theprocess according to claim 1, wherein the hexose oxidase (EC1.1.3.5) iscontacted with the cheese during production of the cheese.
 4. Theprocess according to claim 3, wherein the hexose oxidase (EC1.1.3.5) issprayed on the cheese as a solution or dispersion.
 5. The processaccording to claim 1, wherein the process further comprises contactingthe cheese with a catalase.
 6. The process according to claim 1, whereinthe heating to at least melting of the cheese comprises heating to atemperature of at least 225° C.
 7. The process according to claim 1,wherein the heating to at least melting of the cheese comprises heatingto a temperature greater than 260° C.
 8. A cheese prepared in accordancewith the process of claim
 1. 9. The process according to claim 1,wherein the hexose oxidase (EC1.1.3.5) is contacted with the cheeseafter production of the cheese.
 10. The process according to claim 9,wherein the hexose oxidase (EC1.1.3.5) is sprayed on the cheese as asolution or dispersion.